The remains of the Castle can be visited
Alt-Landenberg Castle (Ruin)

The Alt-Landenberg ruin, a former hilltop castle, is situated on a hill above the Töss river in the municipality of Bauma in the Canton of Zurich.
History+
The origins of Alt-Landenberg Castle date back to around 1200, when it was built as a clearing castle. During this period, the curtain wall was also constructed, and the complex was expanded in several phases, with tuff stone being used. The palas in the eastern part and a three-meter-thick shield wall were added later. The last known knights of the castle fell in 1315 at the Battle of Morgarten fighting for the Habsburgs.
Source: Wikipedia · Licence: CC BY-SA 4.0
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 47.3727, 8.8723